Two studies of vacuums suggest that the speed of light in a vacuum might fluctuate, pointing the way to a quantum mechanical explanation for why the speed of light and other so-called constants are what they are

There are no days off for Olympic hopefuls. If you want to be a champion, you have to practice every single day. The same is true if you want to be a "mentsh." This daily program will help you become a better person by working on a single character trait each week. If one week's area of improvement -- or the author -- doesn't interest you, try another.